High dynamic range assays in hazardous contaminant testing

A lateral flow assay comprising:

• an assay test strip including:
• at least one material configured to wick a liquid sample containing a hazardous contaminant along a lateral flow path extending from a first end of the assay test strip to a second end of the assay test strip;
• a sample receiving zone at the first end;
• a conjugate release zone positioned down the lateral flow path from the sample receiving zone and comprising a plurality of diffusively bound labeled particles configured to be transported along the lateral flow path with the liquid sample;
• and
• a plurality of detection zones positioned sequentially along the lateral flow path, each of the plurality of detection zones comprising a plurality of immobilized capture reagents tuned to fully saturate with the labeled particles at a specific concentration level of the hazardous contaminant, the plurality of detection zones comprising a first detection zone and a second detection zone disposed farther along the lateral flow path relative to the first detection zone, the second detection zone tuned to fully saturate at a concentration different than the first detection zone to account for the liquid sample having flowed through at least the first detection zone;
• and
• a cartridge housing the assay test strip, the cartridge comprising a fluid fitting positioned to provide the liquid sample to the sample receiving zone.